I love the scene from The Untouchables (1987) in which Jim Malone talks to Eliot Ness privately in a church that is Our Lady of Sorrows Basilica in East Garfield Park: 

"You wanna know how to get Capone? They pull a knife, you pull a gun. He sends one of yours to the hospital, you send one of his to the morgue. That's the Chicago way! And that's how you get Capone. Now do you want to do that? Are you ready to do that? I'm offering you a deal. Do you want this deal? ... Well, the Lord hates a coward. ... Do you know what a blood oath is, Mr. Ness?" 

That’s the scene Barack Obama quoted during the 2008 presidential campaign. I always live by the Chicago way.